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More Ways to Blow Things Up

Posted by michael on from the friday-special dept.

pitabutter writes "Since the /. crowd seems to appreciate the exciting combination of amateur chemistry and fearlessness (what is it about intelligence and the desire to blow things up?), Sam Barros' site would be worth a look. Rail guns, high voltage, electromagnetic experiements-all there and with videos to boot. Unable to confirm if Sam still has appendages intact........"

4 of 301 comments (clear)

  1. Build, don't blow... by bobwyman · · Score: 3, Interesting

    The site claims to be: "The number one Amateur Science page!" This is a bit depressing if true. I sure hope that amateur scientists are working more useful problems than blowing things up...
    I can't help thinking about Vannevar Bush's article in the July 1945 Atlantic Monthly in which he surveyed the possible uses for organized technological development and concluded that "Memex" - the source of the hypertext idea, was the most important thing to work on. What would a similar analysis uncover as the most important problem for technology and "Amateur Scientists" today? I don't think it would have anything to do with blowing things up...

    bob wyman

  2. Holy shiznit. by Phanatic1a · · Score: 2, Interesting


    For my senior EE project, I built a railgun. Used aluminmum bar stock for the rails, milled out a channel for a ball bearing, injected the bearing with a paintball gun. The power supply was a bank of electrolytics in parallel totalling 48 mF at 600V, so around 9 kJ total.

    Didn't look anywhere near so impressive as this guy's.

    1. Re:Holy shiznit. by WolfWithoutAClause · · Score: 5, Interesting
      Actually, secretly, he rather overdesigned it; and it works, but doesn't work so well.

      I think out of the hundred meter per second or whatever that the projectile leaves the breech, about 90+% of the speed is due to the gas injector he uses to avoid spot welding.

      The problem is that the pulse of current happens way too early in the gun, and he skids off a lot of his power in arcing.

      He used to run a forum on his website (it seems to be still there, although it doesn't work right now). There was a lot of people, more or less as knowledgeable as him on his forum really interested in trying to help him design it; but he ran roughshod over the lot of them. And they told him about the pulse length issue. So basically they all got majorly pissed off and went off elsewhere in a huff, and they laughed when it didn't go supersonic; well it was Sam Barros's rail gun, but they were trying to help, and he ignored them, and he suffered. Sam had spent too much time going for 'oxygen free copper' to try to improve the current flow, but it didn't help, because but didn't get the fundamentals right.

      But that wasn't the reason they left; it was just the proverbial straw; the problem is that Sam has a few ego problems, atleast online, he may well be more personable in the flesh; but he enjoyed telling people how stupid they were online. Mostly they were too, but few people came back to the site after that kind of treatment; and sometimes Sam was wrong, so he treated them unjustly for no reason.

      So, basically, the powerlabs forum has basically died, all the contributors went elsewhere.

      His basic technical skills are exceptional, although nothing he has done is actually original, so it remains to be seen whether he can achieve his potential, and as anyone can see from the site- he is good.

      --

      -WolfWithoutAClause

      "Gravity is only a theory, not a fact!"
  3. Security through noneducation? by Tuxinatorium · · Score: 4, Interesting

    Seriously, security through ignorance is about as futile as security through obscurity. If High Schools want to water down their chemistry classes in a vain attempt to keep people from learning how to make bombs, I pity them. It's not going to stop a kid who wants to blow up the school from doing so, because the information is everywhere and the materials are common household products. They should just go ahead and teach the kids some cool chemistry with cool demonstrations like methane bubbles, nitrocellulose, thermite, Sugar+KNO3, Zinc+NH4NO3+NH4Cl+H20, etc., all of which I got to do in my AP chem class. :) Plus you can save a lot of money on fireworks around the 4th by making your own ;). Go grab a 20-lb bag of ammonium nitrate, some zinc powder, and then some colorings:
    NaCl (table salt) - orange KCl (salt substitute, road salt) - purple CaCl2 (road salt) - orange Copper - blue
    plus paints are a good source of exotic transition metals, if you can figure out what exactly they contain.

    --
    Repeal the DMCA!